Library inside library

[eluser]Sawariya[/eluser]
one library is---Userauth
class CI_Userauth {

var $obj;

function CI_Userauth()
{
$this->obj =& get_instance();
$this->obj->load->model('user_group_model', '', TRUE);
$this->obj->load->model('remember_me', '', TRUE);
$this->obj->load->library('ua_authorize');
log_message('debug',
'User Authentication Class Initialised via '.get_class($this->obj));
}
}

another one is
class Ua_authorize {

// ACL variables
var $allowed_users = array(); // Allowed Groups and users
var $denied_users = array(); // Denied Groups and users
var $allowed_set = FALSE; // Has set_allowed() been used
var $denied_set = FALSE; // Has set_denied() been used
var $allow = FALSE; // Cuurent status of permission

function Ua_authorize()
{
$this->obj =& get_instance();
}
}